Remove threading from WifiDataProviderCommon.

content/browser/geolocation/wifi_data_provider_chromeos.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_GEOLOCATION_WIFI_DATA_PROVIDER_CHROMEOS_H_
 #define CONTENT_BROWSER_GEOLOCATION_WIFI_DATA_PROVIDER_CHROMEOS_H_
 
 #include "base/compiler_specific.h"
 #include "content/browser/geolocation/wifi_data_provider_common.h"
 
 namespace content {
 
 class CONTENT_EXPORT WifiDataProviderChromeOs
     : public WifiDataProviderImplBase {
  public:
   WifiDataProviderChromeOs();
 
   // WifiDataProviderImplBase
-  virtual bool StartDataProvider() OVERRIDE;
+  virtual void StartDataProvider() OVERRIDE;
   virtual void StopDataProvider() OVERRIDE;
   virtual bool GetData(WifiData* data) OVERRIDE;
 
  private:
   friend class GeolocationChromeOsWifiDataProviderTest;
   virtual ~WifiDataProviderChromeOs();
 
   // UI thread
   void DoWifiScanTaskOnUIThread();  // The polling task
   void DoStartTaskOnUIThread();
@@ skipping 29 matching lines @@
 
   // Whether we've successfully completed a scan for WiFi data. (client thread)
   bool is_first_scan_complete_;
 
   DISALLOW_COPY_AND_ASSIGN(WifiDataProviderChromeOs);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_GEOLOCATION_WIFI_DATA_PROVIDER_CHROMEOS_H_